Bushes, piston rings, seal rings, etc., are built-in various instruments such as hydraulic apparatus, compressors, etc., and these members are required to have sliding characteristics (e.g., low friction, abrasion resistance, etc.).
For the uses which are required to have such sliding characteristics, a sliding member obtained by molding a composition comprising a fluorine resin compounded with glass fibers into a desired form is used by being built-in various instruments as a bush, a piston ring, a seal ring, etc.
As the fluorine resin composition or molded products thereof used for such sliding members, a composition comprising a fluorine resin powder having dispersed therein an inorganic filler such as glass fibers treated with a fluorine-containing silane coupling agent, carbon fibers, etc., and molded products comprising the composition are known as described in JP-A-2-11651 (the term "JP-A" as used herein means an "unexamined published Japanese patent application").
JP-B-3-60857 (the term "JP-B" as used herein means an "examined published Japanese patent application") describes a laminated plate obtained by immersing glass fibers pre-treated with a perfluoroalkylsilane represented by CF.sub.3 -CH.sub.2 -CH.sub.2 -SiX.sub.3 (wherein X represents a hydrolyzable group such as an alkoxy group having from 1 to 4 carbon atoms), sintering the fluorine resin to provide a sheet, and laminating a definite number of these sheets.
Recently, for these various kinds of instruments, the requirement for the improvement of the reliability has been increased and as a matter of course, with such a requirement, the improvement of the performance has been also keenly desired for the sliding members being built-in these instruments. For example, it has been required for the sliding member to improve the abrasion resistance while keeping the low friction (prolonging the life by reducing the abraded amount) under severe use conditions, but conventional sliding members cannot meet the requirement.
That is, the above-described composition and the molded products described in JP-A-2-11651 may have an improved compressive strength but cannot attain the improvement of the abrasion resistance. Further, the laminated plate described in JP-B-3-60857 aims at the prevention of lowering of an electrical insulation resistance but there in no description therein about the abrasion resistance.